This invention relates to connection of data terminals to a data network through wireless access points, and in particular to restoration of such access in the event of failure of a primary connection between an access point and the data network.
Connection to data networks such as the Internet has become an integral part of many domestic and small business activities. Typically, one or more user terminals will connect to the public network through a local area network (LAN) controlled by a router, which mediates data messages between the user terminal and the internet, including providing modem functions. Connection between the terminal and the router may be by an Ethernet or Powerline connection, but increasingly wireless connection is used (a Wireless LAN or WLAN) as this allows terminals to be placed anywhere within wireless range of the router.
Terminals connected to the same router may also communicate between each other without going through the external network. To provide privacy for such activity, and to ensure the router is not misused by unauthorised persons to gain access to the internet, routers typically have access protection to ensure only users with the correct access credentials can use it.
Public wireless access points also exist which allow any users with appropriate terminal equipment to connect to the Internet. These access points may be dedicated public access points provided by commercial enterprises to attract custom, or parts of the capacity of privately-owned access points made available to the public by their owners in exchange for reciprocal access rights to other participants' access points.
Failure of the primary connection between an access point and the network can be problematic as users have become reliant on their internet connections for many business and domestic purposes. In many cases a service provider's helpdesk, or a troubleshooting application, can guide the user to establish a replacement connection to the Internet through a public wireless access point whilst the fault in the primary connection is under repair.
Many troubleshooting operations can be provided by information available on the Internet, but if it is the Internet connection itself which has failed that information is not accessible unless the user has had the foresight to download it in advance. Consequently, such failures account for a very high proportion of calls to network operators' helpdesks—and even that course of action may not be not available if the Internet connection is over the user's telephone line, as the failure is likely to have affected voice calls over the telephone line as well.
The present invention provides a process to allow automatic re-establishment of connection between a user and the data network on detection of failure of the primary network.
It is known, in a related art, to provide for an access point, on detecting a failure of its backhaul (primary) connection, to generate redirection instructions to the wireless terminals currently connected to it. An example of this is described in United States patent application US2011/0032816. However, the system described therein presupposes that the access point has data stored therein relating to the alternative access points to which the terminals should attempt connection. Such an arrangement may be practical in a planned cellular telephone network, where the identities and locations of access points are predetermined by the network operator, and relatively permanent. However, in a network in which access points are under the control of individual users, the availability of such access points is more fluid and unpredictable. Users may move their access points around, or switch them off altogether. In many cases, the access points are provided primarily for the owner's own use, and public access is provided (with suitable firewall protection) only if, and to the extent that, the owner is not using the full capacity. It is therefore not possible, in general, to pre-programme specific redirection instructions in an access point for use in the event of failure of its primary backhaul connection.
A further difficulty with pre-programming data relating to neighbouring access points into the access point itself is that wifi access points have a relatively short range, and a relatively low capacity, primarily intended for individual domestic or business premises. If there is an alternative access point available at all, it is likely that there will in fact be several of them, each with ranges partially overlapping that of the first access point. It is unlikely that any one of them could cope with the extra traffic diverted from the failed access point without a diminishment in service quality to its own customers, or those of the failed access point. It is also likely, as the ranges typically only partially overlap, that the optimum neighbouring access point for reconnection of a data processing device will depend on where that device is located within the area of coverage of the first access point, and indeed the optimum neighbour access point for one terminal may not be the same access point as the optimum for another. According to the present invention, there is provided a process for restoration of network access for a wireless-enabled data processing device initially connected to a data network by means of a first access point after connection between the first access point and the data network is lost, comprising the steps of                a) in the first access point, detecting loss of connection to the data network        b) transmitting instructions from the first access point to the data processing device to cause the data processing device to                    (i) scan for beacon signals from further wireless access points, and            (ii) establish connection to a selected one of the further wireless access points            (iii) establish connection to the data network through the selected further wireless access point                        
This arrangement allows the re-establishment of access to be carried out by the data processing devices themselves. Instead of being given specific redirection routes, they are instead installed with more general programming to allow them each to identify suitable redirection routings for themselves. These devices can therefore each identify the optimum access point to use, taking into account both signal quality and contention from other devices.
It will be noted that the data processing devices can be initially conventional: the search and re-connect functions are installed in the devices by the access point only when and if required. This allows any programmable wireless device that happens to be connected to the access point at the time of the failure of the primary (backhaul) connection to reconnect to another access point.
By having the process initiated by the first access point, in response to detection of a failure in the backhaul connection, re-establishment of connection through an alternative connection is expedited as the data processing devices do not first attempt re-connection through the first access point.
In the preferred embodiment the access point is configured to suspend advertising its presence whilst the backhaul connection is unavailable. This will prevent further wireless devices attempting to connect to it.
In a preferred embodiment, this process is embodied in an application stored in the access point (or other environment available to the terminal while offline) and downloaded to the, or each, terminal connected to the access point whilst the primary connection is detected as being unavailable.
In general public access points give users lower priority than their own dedicated access points. It is therefore also desirable that connection is re-established by way of the primary network as soon as it become available, in order to allow the user the prioritised use that his own access point provides, and also to make the capacity on the public access point available to other users. The present invention provides a process for automatically detecting the reconnection of the primary Internet connection link, and re-establishing connection between the terminal and the Internet by way of that link.
In the preferred arrangement, the access point continues to monitor for availablility of the primary connection, the terminal monitors the access point to identify when connection by way of the primary connection is restored, and restores its settings to effect such reconnection. The application may be arranged to defer such reconnection until any data session in progress has been completed.
It will be noted that although the data terminal must have a wireless capability, it is not necessary for the access point and data terminal to communicate with each other using that capability. The access point and data terminal may be connected by any suitable communication means, such as Ethernet, Powerline etc.
This invention allows users to maintain an active Internet connection during downtime of their main connection with minimal effort, and in particular can access troubleshooting websites to help get the customer reconnected. The invention does not require any pre-installation on the user device of any desktop help applications. In the preferred embodiment the user device downloads application software (e.g using Java), from the router itself, if it is still capable of communication with the user device in order to download the application. If the router is itself disabled, the application may be configured so that if a user device on which the application has previously been loaded detects loss of connection to the WLAN, it may attempt connection by an alternative access point.